CVE-2026-4371

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"unaffected", "version": "0:140.9.0-1.el8_2", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_aus:8.4"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el8_4", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_eus_long_life:8.4"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el8_4", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_aus:8.6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el8_6", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_tus:8.6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8.6 Telecommunications Update Service", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el8_6", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_e4s:8.6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8.6 Update 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"https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:enterprise_linux:9"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el9_7", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_e4s:9.0"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el9_0", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_e4s:9.2"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el9_2", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_eus:9.4"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9.4 Extended Update Support", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el9_4", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_eus:9.6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9.6 Extended Update Support", "versions": [{"status": "unaffected", "version": "0:140.9.0-1.el9_6", "lessThan": "*", "versionType": "rpm"}], "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:10"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 10", "packageName": "rhel10/thunderbird-flatpak", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 6", "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:7"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 7", "packageName": "thunderbird", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}]}], "published": "2026-03-24T21:16:29.583", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2023493", "tags": ["Permissions Required"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-23/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-24/", "tags": ["Vendor Advisory"], "source": "security@mozilla.org"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6188", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6342", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:6917", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8284", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8285", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8286", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8287", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8288", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8289", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8290", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8315", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:8850", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4371", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2451001", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4371.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-126"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-130"}]}], "descriptions": [{"lang": "en", "value": "A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer. If a mail server or connection to a mail server were compromised, an attacker could cause the parser to malfunction, potentially crashing Thunderbird or leaking sensitive data. This vulnerability was fixed in Thunderbird 149 and Thunderbird 140.9."}, {"lang": "es", "value": "Un servidor de correo malicioso podr\u00eda enviar cadenas malformadas con longitudes negativas, haciendo que el analizador lea memoria fuera del b\u00fafer. Si un servidor de correo o una conexi\u00f3n a un servidor de correo fueran comprometidos, un atacante podr\u00eda hacer que el analizador funcione mal, potencialmente bloqueando Thunderbird o filtrando datos sensibles. Esta vulnerabilidad afecta a Thunderbird < 149 y Thunderbird < 140.9."}], "lastModified": "2026-07-15T02:22:39.793", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*", "vulnerable": true, "matchCriteriaId": "4C0558B1-4113-45A8-8E37-A0793A67AD6D", "versionEndExcluding": "140.9.0"}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*", "vulnerable": true, "matchCriteriaId": "40FE4697-89F1-46F6-8E28-41883647583B", "versionEndExcluding": "149.0"}], "operator": "OR"}]}], "sourceIdentifier": "security@mozilla.org"}